I think that the adobe svg plug-in and other software accepts gzip compressed xml which makes it quite compact, so bloatedness is not a valid complaint. On the web we make sure that our web-servers serve all text compressed anyways?
That advantade with xml graphics/svg is that it Is very easy to separate presentation, behaviour and semantics and that custom clients/servers can easily be setup to create/consume the stuff. With flash you are limited to the flash client pretty much.
Compressed bloat is still bloat. The problem here is that XML is a document model, not a data model. Yet people insist on using the screwdriver as a hammer, anyway.
I also don't understand the fascination with making the Web browser a kitchen-sink application, especially when we can't even get the biggest players to render basic HTML and CSS the same way.